FIGS. 1 and 2 illustrate the current substrate 14 design. The current substrate 14 design suffers from a long underfilling cycle time to underfill a chip 10 of, for example, a flow time of about 260 seconds and a self-fillet time of about 570 seconds for a total time of about 830 seconds at about 75° C.
FIG. 1 illustrates a die/chip 10 having solder bumps 12 affixed to the bottom thereof.
FIG. 2 illustrates the die/chip 10 affixed to a substrate 14 and an underfill 16 is injected along the side 11 of the die/chip 10/substrate 14 through dispensing port 20, to underfill the die/chip 10 and create a self-fillet 18. As noted above, this die/chip 10 underfilling time is long and creates a bottleneck in the process flow.
This long underfilling time is due to a low flow rate of the underfill 16 on the solder mask surface and/or underfill voids caused because of air trapped underneath the die/chip 10.
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